Cosmetic surgery is for improving a person's feature. One field of the cosmetic surgery is esthetic dentistry for improving the beauty of teeth. Esthetic dentistry improves the appearance of a tooth of a client by appropriate means, such as orthodontics, tooth extraction, putting in of an artificial tooth, moving of a tooth, removing of a portion of a tooth, bonding of prosthetic material to the remaining portion, and bonding of a prosthetic material to the front side or all sides of a tooth.
A reference used in esthetic dental treatment is dimensions of the first incisors in the maxilla. According to a conventional method, the height of the first incisors to be provided by esthetic dental treatment is 1/16 of the length of a face, and the width of the first incisors is 3/4 of its height. However, the facial length differs greatly from person to person, and the length of the face of a particular person greatly changes as she or he grows older. Accordingly, the determination of an appropriate height and width of the first maxillary incisors on the basis of the facial length is not always successful.
It has been thought to be most desirable to determine the widths of the first incisor, the second incisor and the canine tooth to be in the golden ratio, namely, 1.618:1.0:0.618. On the basis of such conception, sometimes it has been done to combine an image of a row of teeth in the golden section with image of the face of a client to prepare a composite image of his or her face, on which the widths of the teeth can be varied as desired. Then, the client can select the widths of the teeth she or he desires. However, by this method, the widths of the teeth best matching the client's feature cannot always be obtained.
The inventors have determined that the width of the maxillary incisors after the esthetic dental treatment should be determined on the basis of the length of the maxillary denture. When making the invention, the inventors took into account the fact that the length of the maxillary denture is related to the distance between the temporomandibular joints. However, it is difficult to accurately determine these dimensions with equipment installed in common dental clinics. According to the present invention, the distance between the temporomandibular joints is measured indirectly for use in determining the width of the maxillary incisors to be formed by esthetic dental treatment. Also, according to the present invention, dimensions of other teeth to be formed are determined on the basis of the determined width of the maxillary incisors.